Ever since First Great Western introduced a new timetable and withdrew 20 carriages from service on December 10, angry commuters have been contacting the Chronicle with their travel horror stories.

After weeks of frustration at delays and overcrowding, more than 2,000 commuters staged a dramatic fare strike on January 22.

The publicity stunt prompted FGW's managing director Alison Forster last week to issue a public apology, detailing a five-pronged action plan for improvements.

But 11 days on and many users feel the train operator is still failing to deliver.

Peter Andrews, from the Bath and Frome campaign group More Train Less Strain (MTLS), has set up "Train Watch" - a day-by-day log of passengers' experiences on morning rush-hour services.

"What our figures show is that instead of the uniformly ghastly service we were getting before, we are getting a random service," he said.

"One day we'll see the London to Bristol service stop at Oldfield Park and everyone gets a seat and the next day, we're all packed in like sardines again."

Mr Andrews said FGW had been assigning the correct number of carriages to most trains in the past week, but the service remained inconsistent.

"It's totally unpredictable and we're keeping an eye on them but so far, we are very unimpressed," he said.

"It seems to us they are trying to get rid of commuters while improving first-class facilities and this is something we will fight to the end. The battle is far from won."

MTLS spokesman Tony Ambrose said the group had just set up a website, www.moretrainlessstrain.co.uk, where passengers could post comments and ideas for future campaigns.

"We're still nowhere near the services we had pre-December 10," he said.

"We want to see four coaches on every commuter train in rush hour and we want to be sure people can travel in comfort."

But FGW's external relations manager, Adrian Ruck, said the company's performance had improved dramatically since January 15.

"We have got through the maintenance backlog but there are still occasions where services have to be cancelled due to mechanical failures or problems like last week's death on the line at Warminster.

"I'm not making excuses but there are many factors that are out of our control. The track is quite old and this means it is susceptible to mechanical failures."

Mr Ruck said Network Rail was set to invest £750m over the next three years in replacing and renewing track and signalling across the region.

"This will have a dramatic effect on improving the reliability of the service.

"I'm not saying we're not responsible for delays and one-third of them are down to us, but two-thirds are probably due to infrastructure problems."

Mr Ruck said one service where capacity had permanently been increased was the 06.47 Frome to Cardiff train.

"From December 10, it began to run as two carriages but as we reviewed performance it's now back to run as four carriages as a standard change," he said.

"We are now fully up to strength with the number of carriages we have for the regular West Country fleet and since January 15 the number of customer complaints has plummeted.

"There will always be room for improvement and we will continue to monitor performance and are glad to hear from customers."

FGW has said it will be investing £3m on deep-cleaning and improving the interiors of its West Country fleet, £2m more than previously stated.